The CAT5221 is two digital POTs integrated with control logic and 16 bytes of EEPROM memory. Each digital POT consists of a series of 63 resistive elements connected between two externally accessible end points. The tap points between each resistive element are connected to the wiper outputs with CMOS switches. A separate 6-bit control register (WCR) independently controls the wiper tap switches for each digital POT. Associated with each wiper control register are four 6-bit non-volatile memory data registers (DR) used for storing up to four wiper settings. Writing to the wiper control register or any of the non-volatile data registers is via a I²C serial bus. On power-up, the contents of the first data register (DR0) for each of the four potentiometers is automatically loaded into its respective wiper control register (WCR).The CAT5221 can be used as a potentiometer or as a two terminal, variable resistor. It is intended for circuit level or system level adjustments in a wide variety of applications.